Abstract: A method of handling telephone signals supplied by an analog telephone set and data supplied by a data terminal in a subscriber line circuit of a digital telephone switching system used at least in subregions for data transmission includes directly connecting a telephone set and a data terminal with a modem to the digital telephone switching system through a common analog subscriber line, at least one of subjecting data supplied by the data terminal to a sampling operation at a sampling rate above a sampling rate required for telephone information during analog/digital conversion and coding sampling values representing data supplied by the data terminal according to a linear characteristic during analog/digital conversion, and feeding data originating from and handled by the data terminal directly to a data transmission network. A subscriber line circuit for handling telephone signals supplied by an analog telephone set and data supplied by a data terminal is also provided.

Abstract: Differential echo cancellation receiver circuitry with dynamic cancellation of excess DC output current. Differential input circuitry provides for cancellation of incoming DC voltage and the incoming transmit signal echo while passing the receive signal. Excess DC current appearing in the input circuitry as part of the incoming DC voltage and echo signal cancellation is shunted away from the output circuitry with dynamically biased current shunting circuitry that tracks changes in the DC current within the input circuitry.

Abstract: In a method and a device for controlling the magnitude of the generated ring signal in a the Subscriber Line Interface Circuit (SLIC) the voltage of the A and B lines to the subscriber from the SLIC is compared to a reference voltage. The device is arranged to control the magnitude of the generated ring signal voltage in response to the outcome of the comparison. In particular, the device is arranged to control the ring signal voltage so that the ring signal voltage is reduced if the voltage on the A or B line exceeds the reference voltage. Also, the reference voltage is preferably chosen so that there is no risk for saturation of the final stages. The reference voltage is preferably selected to have a value being related to the value of the negative supply voltage.

Abstract: A cordless telephone-to-sound card interface adapter provides a connection between any standard cordless telephone system and a sound card of a computer for PC-to-PC or PC-to-telephone voice communications over the Internet. The interface adapter includes a hybrid transformer circuit for interfacing a two-wire circuit of the cordless telephone and a four-wire circuit of the computer sound card. This hybrid transformer circuit cancels out the voice echo that would otherwise exist due to mismatched impedances between the two media and/or from leakage of the signal being transmitted and received on the same pair of telephone lines. A Universal Serial Bus (USB) plug may be provided to receive a bias voltage from the PC for biasing circuits of the cordless telephone system through the interface adapter. Advantageously, the preferred interface adapter utilizes 100% passive components for a low-cost yet effective means to provide mobility for an end user during voice communications over the Internet.

Abstract: Events that occur in a number of in domain communication channels where each channel is used by a communication service, are detected. A Bayesian Belief Network (BBN) defines a probabilistic cause-effect relationship between each cause and each effect on a victim channel. The probability of each of a number of possible causes as being a cause of interference in the victim channel is determined, by propagating observations of the interference backwards through the BBN.

Abstract: An electronic switching system, comprising a common source of voltage to a plurality of user stations connected in parallel, an electronic means of connection to electrically connect a chosen user station to the common source of voltage, and a means of disconnection command with an optical coupler to control automatically the electronic disconnection of other user stations to the common source of voltage. A default user station is normally the chosen user station. There are means of separation of grounds for the chosen user station and the other user stations.

Abstract: A method for optimizing the transmission properties and power loss of a high voltage part integrated in a subscriber line circuit for connecting a subscriber line wherein, during XDSL data transmission in the high voltage part, current sources which are integrated in the high voltage part and which supply current to the units present in the high voltage part for the purpose of amplifying or measuring telephone signals and/or data signals (which are situated above the frequency band provided for speech), are set, no later than when such data signals are received in the high voltage part, to current values which are higher than the current values for exclusive transmission of telephone signals situated within the voice band provided for speech, such that the data signals within the high voltage part are transmitted with a high bandwidth largely without distortions and the power loss of the high voltage part is optimized.

Abstract: An automated system coordinates, controls and polices installation of customer premise equipment (CPE) for telecommunications services and provides continuing service assurance. The system verifies equipment availability on service request, schedules a qualified technician to install the CPE, and assigns distribution equipment resources to the CPE. The system notifies the technician of the installation date. The equipment resources are auto-assigned to the CPE to facilitate installation procedures. The system also auto-detects installation of the CPE and auto-enables service when the CPE is installed. Customer record creation and maintenance is automatic, and installation or operation of unauthorized equipment is inhibited. Post-installation monitoring and automatic scheduling of repair for system or equipment faults ensures continuing service assurance. The advantage is reduced service delivery time, reduced operations costs and increased customer satisfaction.

Abstract: In an adaptive filter for cancelling common-mode noise in digital subscriber loops, a narrowband noise estimator is used to detect one or more noisy frequency bands of the common mode signal and derive therefrom a first noise estimation signal. A wideband noise estimator derives from the remainder of the common mode signal a second noise estimation signal. The first and second noise estimation signals are subtracted from the differential signal, The wideband noise estimator comprises a bandstop filter for removing the frequencies detected by the narrowband noise estimator, an analog-to-digital converter for digitizing the bandstopped signal, and an adaptive filter for deriving the second noise estimation signal from the digitized bandstopped signal and, in the process, compensating for phase and gain differences, especially attributable to the interference being injected at different points along the length of the channel.

Abstract: The present invention discloses a method and apparatus for reducing the power required by an integrated services hub supporting a plurality of telephone circuits, comprising offsetting ringing of each of the plurality of telephone circuits such that all the telephone circuits do not ring simultaneously. The step of offsetting ringing of each of the plurality of telephone circuits preferably further comprises providing each telephone circuit with a ring cadence comprising a ringing interval and a non-ringing interval and defining a starting point for the ringing interval within each telephone circuit's ring cadence such that the starting point for the ringing interval for at least one telephone circuit falls substantially outside the ringing intervals of the remaining telephone circuits.

Abstract: A method and apparatus is for providing a phantom battery feed to reduce power consumption in a differential amplifier circuit. A voltage signal is driven onto a telecommunications line using a first amplifier and a second amplifier. A phantom battery feed is performed during a negative cycle of the voltage signal. Performing the phantom battery feed comprises: supplying a negative supply terminal of the first amplifier with a supply voltage that is one-half of a full scale supply voltage; and supplying a positive supply terminal of the second amplifier with a supply voltage that is one-half of the full scale supply voltage.

Abstract: The invention relates to a circuit arrangement for forming the termination of an analogous subscriber line which comprises a first connection and a second connection for connecting a twin-wire analogous subscriber line. Said first connection is linked with said second connection via a series connection of a first capacitor, at least one first adjustable resistor and one second capacitor. According to the invention, a direct current source is linked with the first point of linkage of the first capacitor and the first adjustable resistor. Said direct current source impresses a current which serves to adjust an operating point for voice and data transmission via the analogous subscriber line. The first and the second capacitor block equisignals on the subscriber line so that no direct current can flow via the analogous subscriber line.

Abstract: A management system for telecommunication switch is described. The management system is useful for providing operations, administration and maintenance (OAM) functions in a terabit switch. The management system is a scalable management system, whereby processing of large amounts of network management traffic from carrier operators and virtual private network (VPN) customers in a terabit switch is enabled. The management system is efficiently implemented by utilizing surplus processing resources in the network interface cards of the switch. The management system includes a protocol unit residing on a first processor card of the switch for receiving a management request, a first request unit residing on the first processor card for creating a request object in response to the received management request, and a first action unit residing on a first network interface card of the switch for executing the received management request in response to an instruction from the request object.

Abstract: Driver circuit for at least one subscriber terminal, comprising a first driver (14) for amplifying the power of a direct-voltage signal applied for supplying power to the subscriber terminal, the first driver (14) being supplied by a first supply voltage (V1), and comprising a second driver (37; 37a, 37b), following the first driver, for modulating high-frequency signal currents onto the power-amplified direct-voltage signal.

Abstract: A capacitor cancellation method and apparatus for use in an interface circuit having a transformer blocking capacitor. The method includes sensing a voltage across the transformer blocking capacitor and generating a cancellation signal to compensate for the effect of the transformer blocking capacitor. The apparatus includes a sensor to sense a differential voltage across the transformer blocking capacitor to develop a capacitor signal and an amplifier to amplify the capacitor signal to obtain a cancellation signal.

Abstract: Broadband driver circuit for driving voice and data signals, having a current dividing circuit (37), which divides a current generated by a current source (38), in a manner dependent on a voice and data signal present at a signal input (21), into two base currents (Ib1, Ib2) for driving a first driver transistor (39) and a second driver transistor (40), the two driver transistors (39, 40) being constructed identically.

Abstract: A line driver having a non-linear amplifier that is arranged to provide a first output signal, which is an amplified input signal. The line driver also includes an analog linear amplifier providing a second output signal based on the difference between the input signal and the first output signal, placed in parallel with the non-linear amplifier. The line driver also includes a device to combine the first output signal and the second output signal to provide a total output signal to an output line.

Abstract: An RJ 11 port is disclosed that detects the device to which it is connected and automatically reconfigures itself as end user equipment or network interface equipment.

Abstract: A subscriber-line interface circuit (SLIC) has tip and ring amplifiers connected to the tip and ring lines, respectively, of customer premises equipment (CPE). The SLIC returns the ringing signal (provided to the CPE from a power supply connected to the CPE's ring line), to ground or to battery, through the SLIC's tip amplifier. In one embodiment, the SLIC has three switches: S1 connecting the power supply to the ring line, S2 connecting the ring amp to the ring line, and S3 connecting the tip amp to the tip line. During ringing, S1 and S3 are closed to return the ringing signal to ground through the tip amp, which is preferably driven to saturation during ringing to reduce power consumption. By eliminating the fourth switch that appears in prior-art SLICs (e.g., connecting the tip line to ground), SLICs of the present invention can be smaller and therefore less expensive to implement.

Abstract: A digital subscriber line (DSL) compatible plain old telephone service (POTS) line card that interface a telecommunications switching system to a subscriber over a two-wire subscriber line, wherein the subscriber line card detects whether a DSL line card is connected to the subscriber line. A digital signal processor on the POTS line card is configured to process voice-band signals with a first set of parameters if a DSL line card is connected to the subscriber line and to process voice-band signals with a second set of parameters if the DSL line card is not connected to the subscriber line. Detecting the presence of a DSL line card may be performed by sending a voice band tone on the subscriber line and the return loss measured. Additionally, a tone above voice band may be sent on the subscriber line and a return loss measured.

Abstract: A transceiver system is disclosed for use in a telecommunication system. The transceiver system includes a transmission circuit including a transmitter input coupled to an input of a transmission amplifier, a receiver circuit including a receiver output coupled to an output of a receiver amplifier, and a transmission line interface circuit that is coupled to an output of the transmission amplifier and to an input of the receiver amplifier. The transmission line interface circuit includes a matching impedance that is directly coupled to a feedback path of the transmission amplifier and that terminates the transmission line of the transceiver system.

Abstract: A communication system of the present invention utilizes ring detection circuitry on both sides of an isolation barrier. More particularly, the ring detection circuitry may include ring burst circuitry on the phone line side of the isolation barrier and ringer timing circuits on the powered side of the isolation barrier. The digital burst peak signal may be transmitted through the isolation banier to the finger timing circuits. By splitting the ring detection circuitry so that the ringer timing circuits are placed on the powered side of the isolation barriers, a significant reduction in the power usage on the phone line side of the barrier related to the ring detection function may occur. The outputs of the ringing timing circuits may be provided to circuits on either side of the isolation barrier. Thus, the ring detection function may be accomplished in a system utilizing an efficient bidirectional capacitive barrier while still minimizing power usage on the line side of the barrier.

Abstract: Combined plain old telephone system (POTS) and digital subscriber loop (DSL) line card capable of suppressing low frequency transients. The line card includes the following elements. A DSL receive path receives DSL data from a loop. A POTS receive path receives POTS data from the loop. A combined POTS and DSL transmit path transmits POTS and DSL data to the loop. An impedance generator is coupled between the POTS receive path and the combined POTS and DSL transmit path for synthesizing impedance for signals in the combined POTS and DSL transmit path. A low frequency detector selectively applies a high pass filter to an output of the impedance generator for filtering the low frequency transients. Further, a clipped signal detector and a variable pole high pass filter are provided in the POTS receive path. The clipped signal detector in the POTS receive path triggers a switch that discharges stored transient energy in the receive path.

Abstract: Disclosed is a method and apparatus which facilitates the use of existing power that is ordinarily unused or discarded to provide power to a telephone interface circuit when the circuit is in the on-hook state, thereby alleviating the need to use loop current to power the interface during the on-hook state. Existing clock signals are used to charge capacitors that are normally used for capacitive coupling of digital data across the high voltage isolation barrier. Although only small-value capacitors are needed for transmitting data across the capacitive interface, larger-value capacitors are used and are configured to form a charge pump to generate power to the interface at all times. Thus the interface always has a steady source of power available for use, including during the on-hook state for powering circuitry that can detect, modulate, and transmit on-hook signals across the capacitive interface.

Abstract: A communication device has a cut-off frequency switching unit for switching a cut-off frequency for communication data at a communication line, and a confirming unit for confirming whether or not a communication partner has the cut-off frequency switching unit, in advance of sending and receiving of communication data. The confirming unit is structured such that switching control of the cut-off frequency switching unit is carried out in accordance with results of confirmation.

Abstract: An analog front end system comprising a digital-to-analog converter, a line driver, a multiple-input device, and an analog-to-digital converter is presented. Furthermore, a method for DSL line testing comprising the steps of providing test stimuli to and receiving responses from a DSL line using an analog front end is presented. The presented system and method provides for the testing of a DSL line in an xDSL communications system deployment.

Abstract: A protection method and system for equipment in a network element receives a protection request for an equipment item. A priority of the request and a priority of the equipment item is evaluated relative to all other outstanding protection requests for equipment items in a protection group with the equipment item. A highest priority protection request for a highest priority equipment item is performed.

Abstract: A method and apparatus for coupling a voiceband modem circuit to a common phoneline connector, the common phoneline connection having a ring line connection and a tip line connection which couples a ring/tip line pair to a subscriber loop circuit, the voiceband modem circuit operating in a voiceband modem operating frequency band and having a voiceband modem interface ring line and a voiceband modem interface tip line. The voiceband modem interface ring line is coupled to the ring line and the voiceband modem interface tip line is coupled to the tip line connection by inserting, between the ring line connection and the voiceband modem interface ring line and between the tip line connection and the voiceband modem interface tip line, a series pair of inductors. A first inductor of the series pair has a low inductance and a high self-resonant frequency and a second inductor of the series pair has a high inductance and low self-resonant frequency.

Abstract: A modem for Time Division Multiplexed Digital Subscriber Line applications eliminates the requirements for a Hybrid Balanced Network and employs low noise termination of the load resistors using switchable transistors for saturation of the line driver or a switchable parallel balancing impedance activated synchronously with the receive time slot of the TDM protocol.

Abstract: A network termination (NT) which is universally applicable and permits fair billing. The network termination (NT) according to the invention is characterized in that it comprises a switching facility (DET, 1, 2, 3) whereby the interface (a/b, U) on the network side is switchable from an analog one (a/b) to a digital one (U). A subscriber who needs a digital interface, for example because he wants to have two B channels of the ISDN at his free disposal, can release a digital interface (U) or have it released. A subscriber who wants only an analog access can release an analog access or have it released. To accomplish this, the network termination (NT) contains a switch (3) and a detector (DET). The switching between analog access and digital access on the network side can be effected without replacement of the network termination (NT).

Abstract: A line card and method is provided which supports symmetric and asymmetric telecommunication services, such as symmetric and asymmetric DSL services. The line card may support concomitantly POTS and asymmetric DSL services or support DSL services. A xDSL interface provides processing for DSL signals and a POTS interface provides processing for POTS signals. The line card is capable of switching operating modes or which services it is supporting. Preferably, the line card is capable of switching operating modes during a communication session. The line card may switch modes based on instructions received from external devices, such as CPE or far end equipment, based on preprogrammed software or based on operation of the line card.

Abstract: A method provides seamless porting of a user telephone number from a first telephone service provider network to a second telephone service provider network. A network interface device is provided that is interconnected to the first telephone service provider network, a second telephone service provider network, and at least one user communications device. The network interface device may be remotely controlled using the second telephone service provider network to transfer the user telephone number from the first network to the second network.

Abstract: Resistance in parallel with inductors in a series leg of the low-pass filter facilitates changing input and output resistance of the filter with little or no change in the reactance of the inductors. Furthermore, the reactance of the capacitors in the shunt legs of the filter will be substantially unaffected. This assists the designer in matching the impedance of the filter in the pass-band while still providing substantial impedance mismatching in the stop-band without substantially affecting the characteristics of the filter. Facilitating impedance matching in the pass-band and impedance mismatching in the stop-band is accomplished without the need for more complex active components. POTS splitters making use of such filters can facilitate impedance matching of line and load termination in a telecommunications system in response to signals within the frequencies of typical analog telephony service while providing impedance mismatching in response to signals within the frequencies of typical xDSL service.

Abstract: A method and apparatus for pre-qualifying lines with respect to estimating the insertion loss of the line is presented. End-to-end insertion loss at high frequencies is estimated from measurements made at low frequencies through the voice switch at the central office of a telephone company. An AC voltage waveform is applied to the telephone line being tested. Real and imaginary components of the resultant waveform are measured. These measurements are captured and used to estimate the insertion loss of the telephone line at frequencies in the range of 40 kHz to 300 kHz.

Abstract: A technique is provided for an electrical device to automatically detect one of a plurality of interface standards to operate in accordance with. More particularly, a direct access arrangement (DAA) for communicating with telephone lines is provided for utilization with modem communications over a phone line. The DAA may be configured to automatically detect and operate in accordance with a plurality of interface standards for communications to a host system. For example, the DAA may detect that communications are to be provided in accordance with the AC-97 interface standard or the Azalia interface standard. In one embodiment, a clock signal may be monitored to determine the proper interface mode. In another embodiment, the automatic detection of the proper interface mode may be accomplished by monitoring the data presented to the DAA through the interface standard.

Abstract: The invention relates to an SLIC circuit (1), which is connected directly to a telephone line (2), for joint transmission of voice and data via the telephone line (2), with adequate echo attenuation achieved even at high data frequencies in that a first current which corresponds to the sum of the transmission and received currents (Ia, Ib), and a second current (Id) which corresponds to the current produced by the transmission power level (Vtx) at the data frequency, are produced, and the difference between the first current and the second current (Id) is emitted.

Abstract: A protection arrangement for a telephone subscriber line interface circuit is disclosed. The arrangement is particularly useful for protecting an electronic telephone set from over-voltage and over-current fault conditions. The arrangement provides a FET that operates in saturation mode to connect an office battery to the subscriber line under normal operation. The FET also provides isolation capabilities for protecting the line circuit from an over-current condition on the subscriber line. Over-voltage protection is provided by way of an isolation relay between the line circuit and the subscriber line. Both the FET and isolation relay are operated by a controller that uses timers in the methods of over-voltage and over-current protection that it performs. A further capability of the arrangement is that it resets itself after the fault condition has ended. This feature is particularly useful in the case of fault conditions of short duration.

Abstract: An interface circuit including a galvanic isolation barrier between a transmission line and a user equipment, and a detector for detecting, independently from a transmission, the idle or busy state of the line.

Abstract: A transmission channel for a subscriber line interface circuit comprises a front end, tip/ring current-sensing transimpedance stage, containing relatively low valued tip and ring sense resistors coupled in circuit with tip and ring paths of a telecommunication wireline pair. The front end transimpedance stage transforms differential tip and ring input currents sensed by the tip and ring sense resistors into a single ended voltage, which is coupled to a transconductance amplifier filter/gain stage. The filter/gain stage is configured to provide a programmable output impedance, and converts the voltage from the current-sensing transimpedance stage into an output transmission voltage for application to a selected one of a current-sense, voltage-feed, or voltage-sense, voltage-feed telecommunication circuit.

Abstract: A subscriber's telephone system is presented that includes at least one driver circuit connected to Tip and Ring terminals. An additional network is connected between an output of the driver circuit and the Ring terminal. This additional network includes a suitably dimensioned capacitor and a diode limiter connected in parallel with each other to minimize the overall voltage while maintaining a desired battery mean value.

Abstract: A line interface couples signals between a data transceiver and a transmission line having a load impedance Z. The line interface includes a transformer, a driver circuit for supplying a transmit signal from the data transceiver to the transformer, and a receiver circuit for receiving a receive signal from the transformer. The transformer includes a first port coupled to the transmission line, a second port coupled to the driver circuit, a third port coupled to the receiver circuit, a first winding part having a turns ratio of 1: n, where n>1, for coupling the transmit signal from the second port to the first port, and a second winding part having a turns ratio of 1: m, where m<n, for coupling the receive signal from the first port to the third port.

Abstract: A method and apparatus is provided. The method includes receiving a signal over a connection from a telephonic device, determining if the signal is greater than a first preselected value, and adjusting a transient response time of a host transceiver configured to receive the signal in response to determining that the signal is greater than the first preselected value. The method further includes determining a switch hook state of the telephonic device based on a DC component of the signal. The apparatus includes first logic capable of receiving a signal over a connection from a telephonic device, second logic capable of determining if the signal is greater than a first preselected value, and third logic configured to receive the signal, the third logic being capable of adjusting a transient response of the apparatus configured to receive the signal in response to determining that the signal is greater than the first preselected value.

Abstract: A controllably switched arrangement selectively couples multiple circuit functions, such as reverse polarity detection, ring-trip and line voltage measurement, of a telecommunication card to the same external programming component (e.g., capacitor) on an as needed basis, by means of associated coupling circuits and a controlled switching circuit. The coupling circuits are controllably enabled/disabled in association with the particular circuit function required, while the controlled switching circuit selectively connects each coupling circuit with the external component. Through combined control of the coupling circuits and the switching circuit, respectively different circuit functions can be implemented with the same external component.

Abstract: Cascade low-pass filters are useful in attenuating the xDSL band in a POTS splitter. The design of the low-pass filter is a sixth-order filter having two stages. A first stage includes a fourth-order filter, preferably with a stop-band frequency of approximately 48 kHz. A second stage includes a second-order filter in cascade with the fourth-order filter. For this filter, the stop-band frequency is preferably approximately 29 kHz. The inductance value of the second stage is relatively small in comparison to the inductance values of the first stage. In this manner, improvements in xDSL band attenuation are facilitated with little or no eroding of the voice band performance such as insertion loss, pass-band attenuation and return loss.

Abstract: A method and apparatus for measuring signals conveyed by a varying polarity voltage signal across a tip and ring in a telephone system is disclosed. A voltage present across the tip and ring is used to charge a charge storage device, and the charge is periodically discharged for a relatively short amount of time. The burst of discharge current for the short amount of time allows an optocoupler to accurately operate, while presenting a very high impedance to the telephone line.

Abstract: A splitterless interface between a digital subscriber line (DSL) and the central office equipment that can receive and isolate the low frequency voice data and high frequency digital data from a telephone line. This interface can also mix and transmit low frequency voice data and high frequency digital data onto a telephone line. For POTS band frequencies, a reactive impedance coupled across the two-wire interface of the POTS line card, and serially coupled to the line side of the DSL coupling transformer, has an open state magnitude. The magnitude of the line side windings of the DSL coupling transformer is low at POTS band frequencies. POTS band signal power is therefore delivered to the POTS line card. For DSL band frequencies, the reactive impedance across the two-wire interface of the POTS line card has a closed state magnitude. The POTS line card is therefore essentially short-circuited at DSL band frequencies, and DSL band signal power is delivered to the DSL modem.

Abstract: Disclosed are systems and methods for transferring data between servers and subscribers. A central office employs DSL circuit cards. Each DSL circuit card encodes a digital signal using a discreet multitone technology (DMT) scheme, and sends an encoded signal on a subscriber line. A disclosed architecture allows the functions of a faulty DSL circuit card to be assumed by another card, without substantial disruption of subscriber service. Further, the architecture allows the faulty DSL to be physically replaced, with minimal disruption of subscriber service. Another aspect of the architecture allows for the testing of subscriber lines.

Abstract: A method and apparatus for a telephone line interface or data access arrangement (DAA) which includes a shunt regulator in series with a line modulator and a sense resistor. A shunt regulator is placed in series between the sense resistor and the line modulator. The shunt regulator draws power from the telephone line, and the sense resistor senses the amount of current being drawn. The voltage across the sense resistor is fed back to the line modulator. The line modulator is thus capable of adjusting the AC modulation and the DC termination presented to the telephone line based upon the sensed current draw from the telephone line. The telephone line interface can also place an information signal on the telephone line.

Abstract: A DSL access multiplexer exchanges communications between DSL connections and premise connections. A premise wireless interface exchanges the communications between the premise connections and a wireless communication link. A network wireless interface exchanges the communications between the wireless communication link and network connections. The DSL connections, premise connections, and network connections are physically allocated to different service providers. The DSL access multiplexer, premise wireless interface, and network wireless interface maintain physical, spectral, and/or logical separation between the customer communications of the different service providers.

Abstract: Apparatuses and methods are disclosed for communications using current detection. According to one embodiment, a transmitter generates a signal on a transmission line by switching between two power sources. According to one embodiment, the transmitted signal is a balanced signal. Under an embodiment, a signal that has been transmitted on the transmission line is received by a receiver that includes a current detector, and the receiver detects the signal by sensing changes in current on the transmission line. According to one embodiment, the current detector includes a sensor that senses changes in the magnetic field generated by changes in current in the transmission line.